Appendix P - Electrical Safety Program.pdf

Defense Information Systems Agency Electrical Safety Program

UNCLASSIFIED - FOUO Page 1 of 32

Table of Contents

1 PURPOSE

2 SCOPE

3 RESPONSIBILITIES

3.1 Supervision/Management

3.2 Employees

3.3 Contractors

4 REQUIREMENTS

4.1 General Safety Requirements

4.2 Circuit Breakers and switches

4.3 Interlocks

4.4 Ground Fault Circuit Interrupters (GFCIs)

4.5 Energized Electrical Work

4.5.1 Energized Electrical Work Criteria

4.6 Two-person Rule

4.7 Training

4.7.1 Emergency Actions

4.7.2 Contractors

4.8 Personal Protective Equipment

4.8.1 Protective Apparel and Equipment

4.8.2 Insulated Glove Usage

4.8.3 Insulated Line Hose, Sleeves, Mats and Blankets

4.8.4 Insulated Tools and Equipment

4.8.5 Emergency Situations and Electrical Shocks

4.9 Design, Inspection and Restoration

5 REFERENCES

Appendices

APPENDIX 1 Definitions and Acronyms

APPENDIX 2 DISA Energized Electrical Work Permit

APPENDIX 3 Hazard/Risk Category Classifications from NFPA 70E, Table 130.7(C)(9)

APPENDIX 4 Protective Clothing and Personal Protective Equipment (PPE)from NFPA 70E, Table 130.7(C)(10)

APPENDIX 5 Electrical PPE Worksheet

APPENDIX 6 Protective Clothing Characteristics from NFPA 70E, Table 130.7(C)(11)

APPENDIX 7 Approach Boundaries to Energized Electrical Conductors or Circuit Parts for Shock Protection

Attachments

ATTACHMENT A Revision Log

ATTACHMENT B Electrical Safety Program Document Proposal/Clarification Form

Attachment G

UNCLASSIFIED - FOUO Page 2 of 32

1 PURPOSE

This Defense Information Systems Agency (DISA) electrical safety program establishes the safety precautions and responsibilities for safe execution of electrical work from 50 to 600 volts of both Direct Current (DC) and nominal Alternating Current (AC). In addition, systems operating at fewer than 50 volts AC or DC where there is increased hazard from electrical arcing, burns, or high current capacity, are also covered. All work within the scope of this program SHALL comply with the facility work practices. Personal Protective Equipment (PPE), energized work and training requirements are addressed in this plan.

2 SCOPE

This program applies to all employees and contractors at the Facility, who plan, perform, supervise and/or execute electrical work, or work in the vicinity of electrical systems.

This electrical safety program is based on the safety-related work practice requirements outlined in Occupational Safety and Health Administration (OSHA) 29 CFR 1910, Safety and Health Standards for General Industry, 29 CFR 1926, Safety and Health Regulations for Construction Industry, the National Fire Protection Association (NFPA) 70, National Electrical Code® (NEC), Electrical Safety in the Workplace, NFPA 70E®, and Site-specific requirements.

3 RESPONSIBILITIES

3.1 Supervision/Management

Supervision/management SHALL ensure that employees assigned to perform electrical work are trained and qualified to safely perform the work. Tools and PPE required for safe performance of work SHALL be maintained. Supervision/ management SHALL ensure that work involving electrical systems and equipment is de-energized and locked out. If energized electrical work is unavoidable, supervision/management SHALL justify and plan the work activity. A DISA Energized Electrical Work Permit (see Appendix 2) SHALL be in place for every job involving energized electrical work, as defined in section 4.5, unless under exception by this Chapter in Section 4.5.

3.2 Employees

All workers who perform electrical work in the Facility must comply with the PPE and safe work requirements described by this plan. DISA shall notify all contractors performing electrical work in the Facility of the known hazards covered by this electrical safety program. All necessary information required for the contractor to perform their duties shall be made available to accomplish the necessary safety evaluations. In the event that violations of this electrical safety program are observed by the host installation, notification SHALL be made to the contract employee and their employer.

3.3 Contractors

The contractor’s employer SHALL ensure that all hazards associated with assigned work are communicated to the contractor performing the work. The contractor’s employer SHALL ensure that all workers who perform electrical work in the Facility must comply with the PPE and safe work requirements described by this plan. The contractor SHALL immediately report any unique or unanticipated electrical hazards encountered during the performance of their work in the Facility. Corrective measures taken to correct any discovered electrical hazards SHALL be communicated to DISA for correction to prevent future occurrence.

UNCLASSIFIED - FOUO Page 3 of 32

4 REQUIREMENTS

. The requirements include safety requirements of 29 CFR 1910, Safety and Health Standards for General Industry, 29 CFR 1926, Safety and Health Regulations for Construction, and NFPA 70E®, Electrical Safety in the Workplace. Electrical work SHALL be performed by trained and qualified workers, or apprentices under the direct supervision of trained and qualified workers or supervisors.

4.1 General Safety Requirements

All equipment and circuits SHALL be treated as energized until Lock Out/Tag Out (LO/TO) protection is in place and the equipment or circuit has been tested to verify no voltage by authorized workers, or has been physically isolated from every power source, tested, and clearly labeled.

Conductive items like, watches, jewelry, tools, steel tape measures and other conductive materials SHALL NOT be worn or placed on or around energized electrical equipment or circuits.

When working on or near exposed energized parts, approved electrical safety equipment and PPE SHALL be used. Some tasks such as operating high power switches while energized may require safety equipment even without exposed energized electrical components (Reference section 4.8, and Appendices 3). Listed below are some examples of electrical safety equipment and alerting techniques that may be used:

Wear only approved protective clothing, cotton or flame retardant (FR). See 4.8.1.

Appropriate class of rubber insulating gloves, and leather protectors. See 4.8.2.

Rubber insulating blankets and other approved insulating materials.

Voltage testers

Insulated fuse pullers.

Barricades and signs to alert and keep away non-job related, unprotected or unqualified personnel.

Electronic tracers to locate wiring hidden in the ground, floors or walls.

Ground penetrating radar, to locate hidden cables or conduit

Infrared thermography, to identify potential overheated wires and connections.

Control circuit devices, such as push buttons, selector switches, interlocks, building automation or remotely operated systems, SHALL NOT be used as sole means of isolation.

Ensure there is adequate lighting at job site. Utilize temporary lighting, if necessary.

Only non-conductive ladders are approved for electrical work per OSHA regulation 29 CFR 1926.951(c)(1).

Ground fault indications on switchgear SHALL be reported promptly to supervision/management, and repaired as soon as practical.

Capacitors SHALL be discharged and high capacitance elements SHALL be short-circuited and grounded.

UNCLASSIFIED - FOUO Page 4 of 32

Be aware of the possibility of multiple power sources to equipment, or in conduit.

Interlocks between equipment are a likely situation to expect multiple power sources.

Before coming in direct contact with equipment and/or circuits thought to be de-energized, the following SHALL apply:

LO/TO protection or circuit disconnection is completed, as required.

Voltage tester SHALL be a contact type analog or digital multimeter, except as noted below, checked for correct range, then used to test equipment and/or circuits to be worked. Prior to testing of equipment and/or circuits, the voltage tester SHALL be operationally tested on a known energized source for response and to ensure operability. “The before and after voltage tests are still required.

A determination SHALL be made as to the use of grounding device(s) or insulated tools and safety equipment before coming in direct contact with equipment or circuits. This includes de-energized circuits and equipment that needs to be checked for stored or induced electrical energy.

Personnel SHALL NOT enter spaces containing exposed energized parts, unless sufficient illumination is provided to enable safe work.

Personnel required to work in close quarters without adequate clearance SHALL use protective shields, barriers or insulating materials as necessary.

Determine the scope of a pre-job briefing after consideration of the following:

Job plan Voltage Circuit loads Accessibility Complexity of job Need for reference drawings, utility searches Proximity to energized circuits or equipment

4.2 Circuit Breakers and switches

When a protective device such as a circuit breaker trips or fails, operations personnel responsibilities are to:

Inform supervision/management and the manager responsible for the equipment.

Attempt to determine the cause of the trip or failure. An electrician Should be consulted if the cause is not apparent, or 240V and above is involved.

Reset of the device one time is permitted if authorized by the Facility point of contact.

Personnel who are not Trained and Qualified Electrical Workers are allowed to reset protective devices as authorized.

A protective device SHALL NOT be reset a second time unless the cause of the trip is understood and corrected, and has been authorized by the facility.

Resetting protective devices may require flash protection PPE. Reference 4.8.1, and Appendix 3.

All actions taken in association with the tripped or failed device SHALL be documented and reported, as appropriate.

UNCLASSIFIED - FOUO Page 5 of 32

4.3 Interlocks

Only trained and qualified electrical workers, with approval of the Facility Director or his/her designee, may defeat an electrical safety interlock, or a mechanical interlock that restricts access to electrical equipment. The interlock SHALL be returned to its standard position at the completion of work for which it was defeated, unless directed otherwise in writing. Be aware of multiple power sources when working on electrical interlocks, especially between different pieces of equipment.

4.4 Ground Fault Circuit Interrupters (GFCIs)

GFCI protection SHALL be provided for all 125 volt (nominal), single phase 15, 20 and 30 amp receptacle outlets supplying power to portable hand held equipment used by employees in all outdoor applications, in wet or damp locations, and where workers are likely to be well grounded (i.e. mechanical rooms, electrical rooms, etc.) in accordance with 2008 NEC 590.6(A) and (B).

4.5 Energized Electrical Work

Energized electrical work is defined as work performed on or near energized electrical conductors and circuit parts operating at 50 volts or greater. It is also where less than 50 volts is present and increased potential exposure to electrical burn or explosion hazards exist due to electrical arcing, as well as testing of a system thought to be de-energized, but not yet proven to be. (for example, a LO/TO effectiveness check) See “near” in Appendix 1.

Every effort SHALL be made to de-energize electrical systems and equipment prior to work. The Facility LO/TO program SHALL be used to de-energize any control systems and equipment. Electrical conductors and circuit parts SHALL be de-energized before the employee works within the Limited Approach Boundary of those conductors or parts, unless the individual requesting the work can demonstrate that one of the criteria listed in section 4.5.1 apply. Energized electrical conductors and circuit parts that operate at less than 50 volts to ground need not be de-energized where the capacity of the source and any overcurrent protection between the energy source and the worker are considered and it is determined that there is no increased exposure to electrical burn or explosion from electrical arcing

Work on, with, or near megger and high potential (hi-pot) testers, and electric fencing are not considered energized work, due to the extremely low current involved, although contact should be avoided due to startle reaction possibility. For other high voltage low current equipment, the following guidelines apply. If the current is above 5ma, or the energy above 10 joules, then energized electrical rules apply, including LO/TO, and the use of insulated tools rated for the voltage, and dielectric gloves per 4.8.2. If the current is between 0.5 and 5ma, or the energy is between 0.25 and 10 joules, then startle reaction is possible, and should be mitigated by the use of insulated gloves and tools, avoiding contact, or removing or guarding objects likely to cause injury if a startle reaction occurs. Current and energy levels below 0.5ma, and 0.25 joules are of little concern.

Electrical conductors and circuit parts SHALL be considered energized unless they are one of the following.

Disconnected labeled, and verified to be de-energized.

Isolated by a LO/TO and positively determined to be de-energized.

In both cases, a test to verify no voltage SHALL be made by a trained and qualified electrical worker. The voltage test SHALL be with a contact type multimeter, or Volt- Ohm-Meter) adequately rated for the circuit being tested.

UNCLASSIFIED - FOUO Page 6 of 32

CAUTION: “Tic tracers”, “wiggies”, or proximity type testers are not adequate for voltage tests.

The meter must be tested on a known source before making the de-energization measurement, as well as after if the voltage is over 600v. See “Meter Testing” in Appendix 1 for more details.

NOTE: Neutral conductors may show little or no voltage indication even though they may be carrying significant current, since the neutral is grounded at the power panel or source. Measurement with a clamp-on ammeter is recommended.

Before starting work, preliminary inspections and tests SHALL be conducted by a trained and qualified electrical worker to determine the actual condition and state of energization of the electrical conductors and circuit parts. Only qualified electrical workers SHALL be allowed to move energized wires or cables that are part of fixed building wiring. Physical strain SHALL NOT be placed on wires, cables or raceway that is energized or contains energized conductors, or that will be re-energized.

Energized electrical work approval authority and responsibility is vested in the Facility Director or his/her designee(s). All documentation generated by this program shall be retained for the purpose of review and audit by DISA Facilities Engineering.

An electrical supervisor or foreman or site facilities representative SHALL be present during all energized electrical work, at nominal 480V, to directly oversee the work, compensatory safety measures and PPE. A site facilities representative Should be present for energized work at lower voltages.

Authorized written justification for energized work, using the DISA Energized Electrical Work Permit, Appendix 2, SHALL be included as a part of the documentation for performance of energized electrical work. This justification Should have input from the electrical craft. Where less than 50 volts is present but increased potential exposure to electrical burn or explosion exists due to electrical arcing and/or high current capacity, the task SHALL be considered energized work.

Temporary guards, isolation or insulation barriers, such as shields, insulating blankets or tape SHALL be used whenever reasonably possible to protect the worker from the possibility of shock. It is important that the protection be securely fastened in place, so that it cannot be accidentally dislodged.

Anyone performing authorized energized electrical work SHALL have the area around the work cordoned off or barricaded, except as noted below, so that disturbances, UNCLASSIFIED - FOUO Page 7 of 32 distraction, accidental bumping or other physical contact, cannot occur. Bystanders, passers-by, and unprotected, unqualified co-workers SHALL be kept at a specified minimum distance, which is the greater of the Arc Flash Protection, or the Limited Approach Boundary, by these barricades. Qualified personnel SHALL NOT get closer to energized electrical components than the Arc Flash Protection Boundary, unless wearing PPE for Arc Flash Protection. If these barricades do not provide sufficient warning, a person Should be posted to prevent unprotected personnel from entering the area.

An exception to the barricading requirement is allowed for continuously attended LO/TO configuration investigations, LO/TO installation, verification and effectiveness checks, not to exceed 480V nominal, as long as the exposure does not exceed 5 minutes. During this time the Limited Approach and Arc Flash Protection Boundaries required by NFPA 70E must still be enforced by an alternate means. If after 5 minutes, the energized electrical work is not complete, barricading must be set up as required in the preceding paragraph.

The second person, when required by the two-person rule (see section 4.6), may only watch the person performing the energized electrical work, and not enforce the boundary.

This boundary distance is the greater of the Limited Approach Boundary, or the Arc Flash Protection Boundary, for an energized electrical conductor or circuit part, given in the 2009 edition of NFPA 70E, Article 130, Table 130.2(C), for shock protection.

For commonly found voltages in datacenter buildings, the Arc Flash Protection Boundary distances are 4’-0” for systems that are between 50-600 volts, and must be calculated for higher voltages, or fault currents over 100 kA-cycles, or 1667 ampere-seconds.

Calculation information is referenced in 2009 NFPA 70 E, Article 130.3(A).

Bench type work in an electrical shop area is exempted from the barricade or cordoning off requirements, and unprotected personnel access Should be administratively controlled.

Conductors SHALL NOT be installed in, or removed from, raceways containing energized or potentially energized conductors. When conductors are removed from or installed in a raceway with all circuits de-energized (disconnected or under LO/TO), all conductors Should be meggered at their rated voltage before re-energizing any of the conductors, due to the possibility of insulation damage.

Racking in or installing breakers or motor control center “buckets” in or out of an energized MCC or switchgear, or operating switches or breakers on energized switchgear SHALL be considered energized work. The breaker being racked in or installed SHALL be “open” and any power or control wiring that would be subject to strain or damage must be disconnected. Beware that some large breakers have a “test” position when racked out, that disconnects the main power, but leaves control circuits energized for testing.

4.5.1 Energized Electrical Work Criteria

Work on energized electrical conductors and circuit parts may only be approved and performed for one of the following reasons:

For testing or calibration, when tests cannot be done with the circuit or equipment de-energized.

For troubleshooting, when the problem cannot be identified unless the circuit or

UNCLASSIFIED - FOUO Page 8 of 32 equipment is energized. Where possible the equipment SHALL be de-energized while adjustments are made and then re-energized.

When the removal of the power could reasonably be expected to introduce additional or increased hazards, is not feasible due to equipment design or operating limitations, or poses a greater risk to mission critical operations than working on the exposed energized circuits or equipment. In such cases, preference SHALL be given to stopping work, initiating compensatory actions for the work to be done and de-energizing the work area.

NOTE: LOTO effectiveness checks, or pre-LO/TO verifications of correct isolation devices, which include voltage testing, and may include cycling of the isolation device, continuity checks, signal tracing or other methods, are exempt from the energized electrical work permit requirement, as long as no moving, de-terminating or re-terminating of wiring is required. All PPE requirements SHALL apply.

An energized electrical work permit may be repetitively used when incorporated into work that is routine, and not subject to change from job to job.

4.5.2 Energized Electrical Work Permit Exemption

Meter readings, or testing, without moving wires or terminals, and using insulated probes, are allowed without an energized electrical work permit per 2009 NFPA 70E, Article 130. Insulating gloves and other PPE as required by 4.8.1 and 4.8.2 SHALL be worn when performing energized work, regardless of whether a permit is required. All other work, troubleshooting, measurements or testing on or near energized electrical conductors and circuit parts, or equipment operating at greater than 50 volts SHALL be considered energized work and follow the requirements of section 4.5.1.

NOTE: Energized electrical conductors and circuit parts can be observed and assessed by a qualified individual, as long as a safe distance is maintained.

This distance is defined as being outside the Arc Flash Protection Boundary for unprotected, qualified workers. The Arc Flash Protection Boundary SHALL NOT be breached by any uninsulated tool or unprotected body part, and requires an energized electrical work permit, except as previously noted for voltage measurements. Protected qualified employees may work inside of the Arc Flash Protection Boundary from energized electrical parts.

Unqualified and unprotected personnel must remain outside of the Limited Approach Boundary, and Arc Flash Protection Boundary, whichever is greater. Reference sections 4.5, and 4.8 of this chapter, Figure A1 and the definition of “near”, “Arc Flash Protection Boundary”, and “Limited Approach Boundary” in Appendix 1.

For telecommunications workers, energized work approval and presence of an electrical supervisor or foreman or site facilities representative is not required, if ALL of the following conditions are met.

1. Only analog or digital communications) and no other electrical hazards exist, that are not under a LO/TO.

2. Energy release is not “unexpected”, as used in 29CFR1910.147(a)(1)(I). In other words, the worker is handling the conductors as if he/she expects them to be energized.

3. Workers are isolated from ground, grounded objects, or wet locations by insulating

UNCLASSIFIED - FOUO Page 9 of 32 gloves, mats or blankets rated for the voltage involved, and inspected before each use.

4. Insulated tools are used, in good condition, and inspected before each use.

4.6 Two-person Rule

The two-person rule requires the presence of two trained and qualified electrical workers when working on or in close proximity to exposed energized electrical conductors and circuit parts. The two-person rule requires that the first person performs the work while the second person stands by to render assistance, or to summon help for the first person, in the event he/she is inadvertently shocked while performing the work. The second person SHALL be qualified in cardiopulmonary resuscitation (CPR) and know the location of the isolation device(s) for the equipment being worked on. The second person SHALL NOT be assigned to additional duties or tasks while the energized electrical work is being performed. Isolators and verifiers required to work together due to configuration, or other multiple member crews may alternate being the worker or the second person, as long as the second person has no other duties at the time they are acting as the second person. Alternating two electricians may be used to advantage when performing work that requires both wire color recognition, and arc flash protection requiring the green face shield. One electrician may wear a clear face shield, and PPE for low risk work, identify or set up work for the other electrician who wears the green face shield and heavier PPE for higher risk work. They may alternate in their duties as worker and second person as required, to perform the work they are protected for.

4.7 Training

The training requirements contained in this Section apply to workers who are at risk of an electric hazard that is not reduced to a safe level while working on or near energized electrical conductors and circuit parts as a part of their job assignment. Qualified workers SHALL be trained in safety related work practices, emergency procedures, and other requirements that pertain to their respective job assignments. Employees SHALL NOT be permitted to work in areas where they are likely to encounter an electrical hazard unless they have been trained to recognize and avoid these hazards.

4.7.1 Emergency Actions

Employees exposed to shock hazards, as part of their job assignment, SHALL be trained in methods of release of victims from contact with exposed energized electrical conductors or circuit parts. Employees SHALL be regularly instructed in methods of first aid and emergency procedures, such as approved methods of resuscitation, if their duties warrant such training. Training of employees in approved methods of resuscitation, including cardiopulmonary resuscitation, shall be certified by the employer annually.

4.7.2 Contractors

Contractors who employ licensed electricians SHALL be briefed on the Facility specific electrical safety requirements contained in this Program. In addition, written documentation Should be provided by the contractor verifying that the electrician(s) have successfully completed training in accordance with 29 CFR 1910.332, Training.

4.8 Personal Protective Equipment

4.8.1 Protective Apparel and Equipment

When working on or near exposed electrical conductors or circuit parts that are or might

UNCLASSIFIED - FOUO Page 10 of 32 become energized, work practices SHALL be used to protect employees who might be exposed to the electrical hazards involved. Such work practices SHALL protect employees from arc flash and from contact with energized electrical conductors and circuit parts directly, with any part of the body, or indirectly through some other conductive object. The work practices used SHALL be suitable for the conditions under which the work is to be performed and for the voltage level of the energized electrical conductors and circuit parts.

Employees working in areas where there are electrical hazards SHALL use protective equipment that is designed and constructed for the specific part of the body to be protected, and for the work to be performed. Some examples of Personal Protective Equipment (PPE) are listed below:

Hard hat (non-conductive with flame resistant liner) Rubber insulating gloves rated for the voltage being worked Leather protectors for insulating gloves Flame Resistant shirt, pants and coveralls Flame resistant double layer switching hood Safety glasses, goggles or face shield Hearing protection Voltage rated mats, sleeves, or blankets Voltage rated tools Leather work shoes

Where it has been determined that work will be performed in areas where there are electrical hazards, Flame Resistant (FR) clothing and Personal Protective Equipment (PPE) SHALL be used by the employee when working within the Arc Flash Protection Boundary (See definition in Appendix 1). The selection of PPE SHALL be based upon the incident energy exposure (in calories per square centimeter) associated with the specific task.To determine the incident energy exposure (Hazard Category) of the task, the worker Should first review applicable Arc Flash Labeling on the system. If no applicable labeling is applied, the work Should attempt to find the task in Appendix 3, Hazard/Risk Category Classifications. If Appendix 3 is used, the work is assumed to be within the Arc Flash Protection Boundary and actual calculation of the boundary distance is not required. For systems which are 600 volts and below, the Arc Flash Protection Boundary distance is normally 4.0 feet.

NOTE: If the product of fault clearing time and bolted fault current exceeds 100 KA cycles (1667 ampere seconds), the Arc Flash Protection Boundary distance will need to be calculated. Normally this will only apply to building incoming power distribution switchgear, immediately after transformation to 480V, which has the potential for very high bolted fault currents. For systems above 600 volts, and the high available bolted fault current locations noted above, the Arc Flash Protection Boundary distance must be calculated in accordance with 2009 NFPA 70E, Article 130.3.

If the planned task does not match any of the tasks listed in Appendix 3, then a complete Arc Flash Hazard Analysis must be performed when possible in accordance with Article 130.3 and Annex D of NFPA 70E. The Flash Hazard Analysis will determine the Arc Flash Protection Boundary distance and the incident energy exposure. This analysis must be performed by an electrical engineer, as analysis of

UNCLASSIFIED - FOUO Page 11 of 32 fault currents is required. In the event that the required input data is not available to perform an Arc Flash Hazard Analysis, or the specific parameters are outside of the limitations of existing computational models then the work team must determine the applicable Hazard Category to use based on the best information available and expert knowledge.

An Arc Flash Hazard Analysis may optionally be performed even if the planned task matches a task listed in Appendix 3. Performing an Arc Flash Hazard analysis could provide a more accurate determination of the incident energy exposure and possibly reduce the PPE requirements. This might be advantageous if the task will be performed at the lower end of the voltage ranges specified in Appendix 3, or if the task work location is remote from the power source resulting in reduced bolted fault currents (due to wire resistance). An Arc Flash Hazard Analysis may also be performed for arc flashes emanating from outside of switchgear, motor control centers, or other electrical equipment enclosures resulting in an arc in open air.

Once the incident energy exposure (Hazard Category) has been determined, the recommended PPE can be found by referring to Appendix 4, Protective Clothing and Personal Protective Equipment (PPE). If Appendix 3 was used, select the chart that corresponds to the Hazard Category for the task. If an Arc Flash Hazard Analysis was performed, select the lowest Hazard Category Chart that bounds the calculated incident energy exposure. For incident energy values greater than 5 cal/cm2 and equal to or less than 8 cal/cm2, the more conservative Hazard Category 2-asterisk chart Should be used.

Appendix 5, Electrical PPE Worksheet, SHALL be used to document the incident energy exposure and determine the final PPE requirements for the task. The appropriate representative SHALL evaluate the recommended PPE by considering any special circumstances that may influence the final PPE selection. This evaluation SHALL be conducted jointly with the employees who will perform the task. Examples of factors that may influence the decision include, but are not limited to:

The need to distinguish colors accurately may make it impossible to wear a tinted face shield or switching hood during all phases of the task.

The need for manual dexterity may make it desirable to reduce the number of gloves being worn.

Working on a ladder may increase the risk of a fall while wearing a switching hood.

Wearing a switching hood may create an unacceptable heat stress situation.

Awkward positions or cramped spaces may require modifications to the PPE being worn.

The appropriate representative SHALL document any mitigating factors considered in making the final PPE selection and indicate the PPE required for the task on Appendix 2.

In addition, the appropriate representative SHALL document any special instructions for using the PPE on Appendix 2. Special instructions might be required when the specified PPE needs to be modified (or substitutions made) for some of the work steps included in the task.

If the final PPE selected for the task is less than the PPE recommended in the Appendix 4 table, then document the reductions on Appendix 5. The Facility Director or his/her

UNCLASSIFIED - FOUO Page 12 of 32 designee(s) must approve the final PPE selection if it is less than the PPE recommended in the Appendix 4 table, and SHALL indicate approval by signing the Energized Electrical Work Permit.

Additional copies of Appendix 5 SHALL be used for each energized work task that results in a different Hazard Category. A single work evolution may have multiple copies of Appendix 5 to cover all of the energized work tasks.

The completed PPE worksheets are attached to the DISA Energized Electrical Work Permit (see appendix 2). In those cases where an Energized Electrical Work Permit is not required, the PPE worksheets are filed with the Facilities Point of Contact.

For repetitive electrical work, such as circuit breaker operation, or work covered by procedure, a generic Appendix 5 can be developed. Once completed, the generic Appendix 5 for repetitive work remains effective unless a change in the job activity or the analyzed hazards necessitates a re-evaluation of the original PPE selection. Prior to performing the work activity, the appropriate representative SHALL review the approved Appendix 5 to ensure adequacy. A copy of the approved Appendix 5 SHALL be available at the work site.

Protective equipment and clothing SHALL be maintained in a safe, reliable condition. The protective equipment SHALL be visually inspected before each use. Protective equipment and clothing that is soiled, or contaminated with grease, flammable or combustible liquids, or is damaged or worn SHALL be removed from service, and cleaned, repaired or discarded, as appropriate. Workers SHALL be trained in the proper use and care of all safety apparel and equipment they are required to use.

The PPE requirements of this section are intended to protect a person from arc-flash and shock hazards. While some situations may result in burns to the skin, even with the protective equipment prescribed in the charts, any burn injury should be relatively minor and survivable. Due to the explosive nature of some arc events, physical trauma injuries may occur. The PPE requirements of this section do not provide protection against physical trauma.

4.8.2 Insulated Glove Usage

All insulated gloves SHALL have a valid test date whenever they are used. All gloves ordered new Should be specified to have the manufacturer’s test date included, as this is not required by the glove standard ASTM-D120. If the manufacturer’s test date is over 6 months old, and the gloves are sealed in the original package, the gloves SHALL be inspected for any signs of degradation before being marked with the expiration date.

Any visible degradation such as cracking, checking, pitting, swelling, hardening, stickiness or inelasticity SHALL be cause to destroy and discard the glove. If the manufacturer’s test date is 12 months or more before the date to be issued, the test date cannot be determined, or the original package is not sealed, the gloves must be electrically re- tested before issue, or discarded. Class 00 and 0 insulated gloves will be marked with an expiration date on the cuff at the time they are first placed in service (removed from the manufacturer’s packaging). The date entered will be six months after the day they are placed in service. Class 1 through 4 gloves may be similarly marked, or have the test date entered in a log that is tied to the gloves by a serial number or other reliable means.

At each usage the gloves will be visually inspected for deterioration or damage and verified that the expiration dated has not been exceeded. Additionally the gloves will be

UNCLASSIFIED - FOUO Page 13 of 32 verified not to contain holes by the performance of an air leak test prior to each use.

Gloves that have exceeded the expiration date SHALL be re-tested for dielectric characteristics before being used again, or discarded. Gloves used without leather protectors SHALL be electrically re-tested before re-use with leather protectors at the higher voltage allowed with leather protectors. After re-testing, 0 and 00 gloves will be marked with a new expiration date that will be six months after the test date. Class 1 through 4 gloves may be similarly marked, or have the test date entered in a log that is tied to the gloves by a serial number or other reliable means. The test date is the ruling date, not the issue date, except when first placed in service.

Table 1, Insulated Glove Usage, indicates glove class relative to the leather protectors required. Leather protectors are required in all cases where the possibility of damage or puncture of the insulating glove exists.

Table 1 - Insulated Glove Usage

Glove Class Leather Protectors Used (No or Yes) Class

00 No, 0 V to 250 V ---------Yes, 0V to 500 V

Class 0 No, 0 V to 500V-- --------Yes, 0V to 1000V

Class 1 No, 0 V to 1,000 V –----- Yes, 1,000 V to 7,500 V

Class 2 No, 1,000 to 7,500V –--- Yes, 7,500V to 17,000V

Class 3 No, 7,500 to 17,000V –- Yes, 17,000V to 26,500V

Class 4 No, 17,000 to 26,500V – Yes, 26,500 V to 36,000V

4.8.3 Insulated Line Hose, Sleeves, Mats and Blankets

Insulating blankets, matting, line hose and sleeves made of rubber SHALL be seamless, and marked with the voltage class 0 through 4. These insulating devices SHALL be inspected for damage before each day’s use, and after any incident suspected to have caused damage. In addition, insulating blankets and sleeves SHALL be tested every 12 months, maximum, and the expiration date, which is 12 months after the test date, applied to the equipment. Testing is to be per the requirements listed in 29CFR 1910.137, and ASTM F 496. Any of these may be cut into smaller pieces; either to eliminate damaged portions, or to fit a particular application, provided the voltage class and expiration dates are transcribed to each piece.

4.8.4 Insulated Tools and Equipment

When working on or near exposed energized conductors or circuit parts, each employee SHALL use voltage rated insulated tools or handling equipment if the tools or handling equipment might make contact with energized electrical conductors and circuit parts.

Insulated tools SHALL be used in addition to PPE.

Factory manufactured insulated tools, connectors, or adapters rated for the voltage involved, SHALL always be used where available.

4.8.5 Emergency Situations and Electrical Shocks

All electrical shocks (excluding static electricity) are considered medically serious and SHALL be reported to supervision immediately. Even if the victim shows no apparent signs of injury, he/she SHALL be escorted to a medical facility. Supervisors SHALL report shock incidents or electrical emergencies to responsible contractor supervision, if

UNCLASSIFIED - FOUO Page 14 of 32 applicable, and the Facility Site Director as soon as possible.

4.9 Design, Inspection and Restoration

Any modification or new installation of electrical systems or equipment SHALL have an electrical inspection by a qualified individual. (See definition in Appendix 1) All modifications and new installations SHALL comply with the applicable requirements set forth in the latest edition of the NEC, except where code requirements are exceeded, as noted on construction specifications, construction drawings, or as specified in Department of Defense (DOD) Orders or DISA standards.

Listed and labeled electrical equipment, systems, and components SHALL be used where available, and SHALL be installed in accordance with any instructions included in the listing and labeling. Listing and labeling must be performed by a Nationally Recognized Testing Laboratory.

Meggering of new wiring, or wiring being re-energized after being disturbed, is strongly recommended. Meggering does not need to be treated as energized work, due to the small current applied (on the order of 1 milliamp), and the small amount of energy involved. Precautions should be taken to avoid electrical shock, as the voltage level is sufficient to startle and cause involuntary movement.

Return equipment or circuit to operation after repair or modification as follows:

1. Reconnect all disconnected wiring.

2. Remove all static or induced power grounds on the “hot” conductors, if installed.

3. Test circuit or equipment for grounds or faults.

4. All test equipment, tools, ladders, and temporary lighting removed from equipment or circuit.

5. Verify equipment grounds are intact.

6. Secure all electrical panels and doors, and remove LO/TO.

Energized electrical conductors and circuit parts of electrical equipment operating at 50 volts or more SHALL be guarded against accidental contact by OSHA compliant means.

Electrical installations having exposed energized electrical conductors and circuit parts SHALL be accessible only to qualified persons.

Temporary electrical power and lighting SHALL comply with the requirements specified in the NEC.

Flexible cords and cables SHALL be approved and suitable for conditions of use and location. Flexible cords SHALL NOT be used as a substitute for the fixed wiring of a structure and SHALL be protected from accidental damage, and arranged to not be a tripping hazard. NEC disallows using raceways to support flexible cables, except in certain conditions. Reference NEC 300.11(B).

All electrical splices and joints and the free ends of conductors SHALL be covered with insulation equivalent to that of the conductors, or with an insulating device suitable for the purpose.

High voltage warning signs SHALL be posted where other than qualified persons might come into contact with energized electrical conductors and circuit parts.

NEC grounding requirements for electrical systems SHALL be strictly adhered to as a

UNCLASSIFIED - FOUO Page 15 of 32 minimum requirement. The path to ground from circuits, equipment and enclosures SHALL be permanent and continuous. In addition, new installations require an equipment ground running with the circuit conductors.

Working clearances, access, illumination and headroom, as defined in the NEC, SHALL be established and maintained around electrical equipment.

All unused openings in cabinets, boxes and fittings SHALL be effectively closed.

Wiring and components installed in hazardous (classified) locations, as defined in the NEC, SHALL be installed in accordance with the latest edition of the NEC.

Circuit and equipment labeling SHALL be performed in accordance with the current DISA Labeling & Identification Specification. De-energized, de-activated and abandoned equipment, conduit and wiring SHALL be identified with tags of any durable material, or color-coded, where the meaning of such is clear to persons working in the facility per NFPA 70, NEC requirement.

5 REFERENCES

ASTM F496, Standard Specification for In-Service Care of Insulating Gloves and Sleeves

NFPA 70, National Electrical Code®

NFPA 70E, Standard for Electrical Safety in the Workplace®

29 CFR 1910, Safety and Health Standards for General Industry

29 CFR 1926, Safety and Health Regulations for Construction

UNCLASSIFIED - FOUO Page 16 of 32

APPENDIX 1

Definitions and Acronyms

(Page 1 of 4)

1.1 SHALL, Should, and May Statements

The word SHALL identifies those mandatory requirements or actions. The word Should indicates a recommendation that is based on standards and good safety and business practices. The word may indicates when permission is granted, but the action is neither a recommendation or a requirement. May statements often provide a suggested or possible course of action when a consistent methodology is not required. For emphasis, these terms appear in boldface throughout this document.

1.2 Definitions

Arc Flash Protection Boundary. When an arc flash hazard exists, an approach limit at a distance from a prospective arc source within which a person could receive a second degree burn if an electrical arc flash were to occur.

ATPV or Arc Thermal Performance Value. This is the rating of a protective garment or shield in calories per square cm. It is the maximum amount of energy that can be incident on a fabric or shield without it breaking open, or transmitting heat that would cause more than a second-degree burn. (A second-degree burn is curable with just blistering) This implies that the fabric or shield does not continue to burn after the arc has subsided, only chars.

Bolted fault current. The maximum current flow possible with a very near zero resistance fault, equivalent to two wires with lugs bolted together. Current flow is limited only by a combination of wire resistance, and the secondary impedance of the transformer that feeds it.

Electrical Supervisor (or Electrical Foreman). As used within this document, an Electrical Supervisor or Electrical Foreman SHALL have experience as an electrician, lineman, or engineer.

Energized Electrical Work. Work performed on or near energized electrical conductors and circuit parts or equipment with exposed components operating at 50 volts or greater.

Also where less than 50 volts is present and increased potential exposure to electrical burn or explosion hazards exist due to electrical arcing. Also testing of a system thought to be de-energized, but not yet proven to be (for example, a LO/TO effectiveness check).

See “near” in Appendix 1.

Exposed (as applied to energized electrical conductors or circuit parts). Capable of being inadvertently touched or approached nearer than a safe distance by a person. It is applied to electrical conductors or circuit parts that are not suitably guarded, isolated or insulated.

Insulated Tools. Tools tested and approved by the manufacturer for the rated voltage or tools that are covered, surrounded or separated with a nonconductive material in order to prevent or reduce the transfer of electricity, and are rated to a specific voltage.

UNCLASSIFIED - FOUO Page 17 of 32

For power tools, the term “single insulated”, and “double insulated” refer to the insulation layers between the power to operate the tool (usually 120V), and the case of the tool held by the worker. They in no way refer to any voltage rated insulation between the blade or bit at the point of operation, and the case. For single insulated tools, the ground wire (the 3rd prong on the plug) is sized and rated to conduct current expected by a fault in the tool from the operating voltage (usually 120V) to ground. It may not be adequate to provide a ground from a higher voltage placed on the case of the tool from cutting into a higher voltage wire. (An example is cutting into a 480V wire with a 120V powered tool).

Lift Leads and Cut Back Terminology used to denote disconnecting leads, and cutting the leads back, so that they can’t readily be re-connected to a source of power. Labeling as to previous use or destination, and if de-energized is recommended. After lift leads and cut back has been done at the supply breaker or disconnect switch, a LO/TO applied to the supply could be removed, and the switch or breaker re-labeled as a spare.

This terminology could also be applied to wiring connected to an intermediate point, or load end of a circuit. Leads that have been lifted and cut back SHALL be treated as energized until individually verified to be de-energized, and Should be labeled as “lifted and cut back” where not obvious.

Limited Approach Boundary. An approach limit at a distance from an exposed energized electrical conductor or circuit part within which a shock hazard exists.

Nationally Recognized Testing Laboratory. An independent testing laboratory. UL, (Underwriters Laboratory), FM (Factory Mutual), and CSA (Canadian Standards Association) are the main approved testing laboratories that can approve electrical components in accordance with OSHA requirements.

Near. Conditions where contact with exposed energized components is possible by slipping, tripping, falling, actions of others, or inadvertent action of reasonable probability. For electrical panels, with exposed electrical components at 50V or greater, breaking the plane of the panel with any tool (except insulated meter probes) or body part is considered “near.”

Permanent GFCI. A GFCI breaker installed in a power panel, or an outlet type GFCI installed in an outlet box. The GFCI will have a gang type configuration, meant to be installed in an outlet box.

Prohibited Approach Boundary. An approach limit at a distance from an exposed energized electrical conductor or circuit part within which work is considered the same as making contact with the electrical conductor or circuit part.

Portable GFCI. A GFCI listed and identified for portable use, and usually has a pigtail on one or both of the male and female connectors. The GFCI is commonly enclosed in a molded case.

Qualified Individual. A person whose formal education and work experience give them an in-depth knowledge of electrical equipment, methods of electrical construction, codes, and maintenance, both from an operational and safety standpoint. This may include electrical engineers, electrical supervisor or foreman, electricians or technicians with the above qualifications.

UNCLASSIFIED - FOUO Page 18 of 32

Raceway. An enclosed channel of metal or nonmetallic materials designed expressly for holding wires, cables, or bus bars, with additional functions as permitted in the National Electrical Code. Raceways include, but are not limited to, rigid metal conduit, rigid nonmetallic conduit, intermediate metal conduit, liquid-tight flexible conduit, flexible metallic tubing, flexible metal conduit, electrical nonmetallic tubing, electrical metallic tubing, underfloor raceways, cellular concrete floor raceways, cellular metal floor raceways, surface raceways, wireways, and busways.

Restricted Approach Boundary. An approach limit at a distance from an exposed energized electrical conductor or circuit part within which there is an increased risk of shock, due to electrical arc over combined with inadvertent movement, for personnel working in close proximity to the energized electrical conductor or circuit part.

Trained and Qualified Electrical Worker. A person with a demonstrated knowledge of the operation,…